7-27.1 An Overview of the Computer Link Function7.1.1 What is the Computer Link Function?A computer link is a function that enables a computer to read data from, and write data to, the I/O orregister of a programmable controller, and to read from and write to the contents of the registers andprograms in the controller.An interactive communication procedure (protocol) called MEWTOCOL-COM is used for the computerlink.Communication is carried out by the computer sending command (instruction) messages to theprogrammable controller and receiving response messages from the programmable controller.When the programmable controller receives a command message, it automatically returns a responsemessage.After a connection has been opened, there is no need to create a program on the programmablecontroller side to handle communication.Key Point:- With a computer link, the programmable controller specifies an IP address and a MEWTOCOL stationnumber (1 to 64), and opens a connection with the computer (partner node) in the MEWTOCOLcommunication mode.- A computer link enables up to eight simultaneous connections, in conjunction with other communicationfunctions, using a single ET-LAN unit.- The computer link function and data transmission function can be run on the same connection at thesame time.
